1. Field of the Invention
the present invention relates to a magnification change-over device for a camera, and more particularly to a magnification change-over device for camera which allows a variable power camera to be provided having a small size and a lower cost.
2. Description of the Related Art
A number of different kinds of variable power cameras (cameras with variable magnification) which can make a long focus photographing and a short focus photographing, have been proposed to date. However, conventional variable power cameras have such drawbacks that a zooming mechanism and a lens change over mechanism are located around a lens barrel. Thus, the size and bulk of the camera becomes larger. Also since the lens barrel portion moves largely back and forth along with a magnification changing operation, a mechanism for light shielding becomes complicated resulting in a very high cost.
Contrary to this, the present invention has proposed a magnification change-over device for a camera which provides a small size variable power camera at a low cost wherein the above-mentioned drawbacks are eliminated, and has filed U.S. patent application Ser. No. 866,328 filed May 22, 1986, now pending therefor. An arrangement of the camera of this application is as shown in FIGS. 6(a) and 6(b).
FIG. 6(a) shows the state of each portion of a camera at the time of a short focus photographing, while FIG. 6(b) shows the state when a long focus photographing is made. What is shown as 1 is a camera body, and 2 is a back lid. Within the camera body 1, a battery chamber 1d and a spool chamber 1d, a film cartridge chamber 1e are formed, and, at the same time, an aperture 1f for long focus photographing and an aperture 1g for short focus photographing are provided along a running direction of a film F in a manner adjacent to each other. A photographic lens with a convex lens system comprising lenses 17 to 19, is supported by a lens frame 16, which is fixed within a lens barrel 1c of the camera body 1. A front lens 22, which can move within the lens barrel 1c in the lateral direction, is provided in front of the photographic lens, the front lens 22 being fixed to a movable frame 21. What is shown as 23 is a movable mirror used when a long focus photographing is done, and 24 is a converter lens used when a long focus photographing is made, while 25 is a fixed mirror used also when a long focus photographing is made.
When a short focus photographing is made, the movable mirror 23 and the front lens 22 are placed in the state shown in FIG. 6(a), and the bundle of light from an object passes through the lenses 17 to 19 and is imaged on the aperture 1g for a short focus photographing. On the other hand, when a long focus photographing is made, the movable mirror 23 and the front lens 22 are places in the state shown in FIG. 6(b), and the bundle of light from an object proceeds through a Z shape optical path formed by the front lens 22, the lenses 17 to 19, the movable mirror 23, the converter lens 24, the fixed mirror 25, and the aperture 1f for a short focus photographing, and is imaged at the aperture 1f.
According to such arrangement, a zooming mechanism and a lens change-over mechanism are not located around a lens barrel as in a conventional variable power camera, thus a camera can be made to have a small bulk and size. Further a lens barrel part will not move largely back and forth along with a magnification changing operation, thus a drawback of complicating the mechanism and increasing a cost, and is characterized will be eliminated.